Answer:
B. abiotic factors.
Explanation:
Abiotic factors describe soil and temperature in an ecosystem.
Receptors<span> are generally transmembrane </span>proteins<span>, which bind to signaling molecules outside the cell and subsequently transmit the signal through a sequence of molecular switches to internal signaling pathways</span>
Reproduction is the process of making copies.
In an office, the photocopy machine reproduces documents.
In nature, people, plants, and animals reproduce themselves,
and their species continue on Earth when they die.
FOOD CHAINS FOLLOW A SINGLE PATH AS ANIMALS EAT EACH OTHER.
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